Sounder.



E. G. WOOD.

SOUNDER.

APPLICATION FILED SEPT. 22, 1909. 1,035,292. Patented Aug. 13, 1912.

9 SHEETS-SHEET l.

\X/FFNEEEES: IHVENTCJR;

M64 MAM) E. O. WOOD.

SOUNDER APPLICATION FILED SEPT.22, 1909. 1,035,292. Patented Aug. 13,1912.

9 SHEETS-SHEET 2.

I I I IHH H J [WWII E. G. WOOD.

SOUNDBR.

APPLIOATION FILED SEPT, 22 1,035,292.

Patented Aug. 13, 1912.

9 SHEBTS-SHEET 3.

II II II II ig- I INVENTEH Jae. $90M lwu aw) E. G. WOOD.

SOUNDER. APPLICATION IILED SEPT. 22, 1909.

1 ,035,292. Patented Aug. 13,1912.

9 SHEETS-SHEET 4.

iii:

\X/I'THEE 5 E m ff Ti: H:

E. O. WOOD.

SOUNDER.

APPLICATION FILED SEPT. 22 1909.

9 SHEETS-SHEET 5.

Patented Aug. 13, 1912.

Fig .1EI

FTEJZ. \X/ITNESEEE E. G. WOOD.-

' SOUNDER. APPLIGATION TILED SEPT. 22, 1909.

1,035,292, Patented Aug. 13,1912.

9 SHEETS-SHEET 6.

E. C. WOOD.

SOUNDER.

APPLICATION FILED SEPT. 22, 1909. 1,035,292. Patented Aug. 13,1912.

9 SHEBTS-SHBET 7,

'7 Z Fi 14 @2115. WITNEESEE: IHVEHTDFE c. WOOD. SOUNDEB.

APPLICATION FILED SEPT. 22, 1909. I 1,035,292. Patented Aug. 13, 1912.

9 SHEETS'SHEET 8.

E. U. WOOD.

SOUNDER.

APPLIGATION FILED snrmzz, 1909.

Patented Aug. 13, 1912.

9 SHEETS-SHBET 9.

- To all whom it may concern:

ITED STATES PATENT OFFICE.

EDWARD C. WOOD: 0F SOMERVILLE, MASSACHUSETTS, ASSIGNOR TO SUBMARINESIGNAL COMPANY, OF WATERVILLE, MAINE, A CORPORATION OF MAINE.

SOUNDER.

Specification of Letters Patent.

Patented Aug. 13, 1912.

Application filed September 22, 1909. Serial No. 519,079.

Be it known that I, EmWARn C. 7001), of Somerville, in the county ofMiddlcsex and State of Massachusetts, a citizen of the United States,have invented a new and useful Improvement in Sounders, of which thefollowing is a specification.

The especial purpose of my invention is to secure an apparatus forsubmarine signaling which shall be simple and upon which code signalscan be sounded of sufiicient strength to be heard a number of miles.

A submerged bell percussively struck has proved satisfactory in manycases for producing submarine signals as, for example, when attached toa buoy, a lightship, a pier or a tripod on the sea floor or otherstationary object and employed as a coast warning or guiding signal. Ithas also proved effective in many other cases. For signaling from onerapidly moving ship to another,

' however, a bell has not proved so satisfactory as for a coast warningor guiding signal. Moreover a sound carrying far enough to give ampleWarning to a moving ship when sent from a lightship or other stationaryobject may not carry far enough to give an ample warning when sent froman approaching ship, as the speedof the two ships reduces the time ofwarning. For communicating messages by code a percussively struck bellis not so satisfactory as a l sounder which can produce signals of anydesired duration. For if the duration of a sound of constant strengthcan be controlled it becomes possible to use it in any system of codesignaling such as for transmitting messages by the-Morse alphabet.Moreover the introduction of signals of any desired duration makes itpossible to distinguish signals sentv from fixed points from those sentfrom moving ships, should such a distinction seem desirable. In otherwords, the addition of a new type of signal, viz: one comprisingcontinuous sounds of any desired duration, adds another factor tosubmarine signaling which materially increases its possibilities. Tosecure such results I have-invented a sounder which is, broadlyspeaking, new in that the means whereby it is operated is a plurality ofenergizing elements each of which acts in turn to attract a diaphragm sothat the diaphragm is alternately attracted and released and so set insufficiently rapid vibration to produce sound 7 attached to it. In thiscase the "ibration of the armature is caused by the alternate increasingand diminishing of the magnetic force acting upon the diaphragm itselfor a piece of iron or other magnetic material attached to the diaphragm.By proportioning the diameter and thickness of the diaphragm to thespeed of the passage of the magnets, vibration of the-diaphragm may beset up which will cause a strong musical note capable of transmissionfor 'a long distance, and this note will continue so long as magneticfields of sufficientstrength pass in actuating relation to it, but itmay be interrupted at any time by diminishing the strength of the fieldsor changing their relation to the diaphragm. My invention equallycontemplates the use of an'electromagnet attached to the diaphragm andthe passage of a plurality of armatures within the attractive reach ofthe magnet.

In the above statement of my invention I have for the sake of simplicityused the word diaphragm in reference to the soun'd producing body. Myinvention, however, also contemplates the use of a bell, reed, plate orany form of sound-producing vibrator, and I shall hereinafter use theterm vibrator for the purpose of including such devices.

In the simplest form of my invention now known I use a rotaryelectro-magnet constructed of two soft iron disks side by side andconnected by a core, a helix or exciting coil placed about the corejoining the'two disks, the disks having teeth out in their peripheriesso as to form projections located opposite to each other and in closeproximity to each other. On passing. a current through the helix thedisks will become magnetized and fields formed at the teeth. In rotatingthe magnet near a soft iron armature attractive impulses will be set upat the period at which each pair of teeth pass the frequent purposes onsuch boats.

armature. High periods of vibration may be created, as a magnet of thisconstruction may have many teeth or projections and berotated with greatrapidity. In this method of exciting a body one does not encounter thedifiiculties of magnetic lag or hysteresis, and counter electro-motiveforce. As it is necessary to use a high degree of-power to establishsubmarine sounds and at the same time it is impracticable to produce"magnetic impulses at a high rate of vibration by repeated interruptionsof the large electrical currents necessary, I have in this mannerconstructed a magnet in which the current can be constantly flowing, andthe impulses of the vibrator can be brought about by the movement pastthe armature of its magnetic fields. long as current passes through the.coil. When the current is interrupted the poles lose their magnetism,and the diaphragm ceases to originate sound waves of signaling value;infact, it usually'becomes silent, taking up its work again the momentthe electric current-again passesthrough the coil. The interruption ofthe current is thus utilized not for causing the magnetic impulses bywhich each vibration of the diaphragm is caused, for such vibrations arecaused by the approach and recession of the magnetic fields, but for theseparation of one period of active vibration from another so that codesignals may be sounded. The code mechanism therefore comprises a.circuit breaker by which the current which energizes the magnet isinterrupted, and this circuit breaker may be operated automatically orby a hand-operated key. In the former case the. sounder willcontinuously give out signals of predetermined character-and in thelatter case may be caused :to give out signals which Wlll enable thesender to communicate information of any character to any person onboard ship or at a shore station who has the now well known instrumentsfor receiving submarine sound waves. The system thus indicated is welladapted for installation and use upon submarine boats as it requlres butlittle room and is operable by power of the character utilized for otherIt will be seen that this invention may be embodied in various ways. Insome forms of my invention the magnet might theoreti cally be apermanent magnet, .but practically 'an electro-magnet is the simplestand bestas 1t 1s much more powerful and is constant in strength. Thevibrator may be in itself sub ect to magnetic attraction, e. 9. made of,soft'iron, or it may carry one or more ar1natures. Moreover a similarresult may be secured by placing a single magnetupon the v1brator,-us1nga number of armatures with "means to cause them to approach and recedefrom thevibrator in rapid succession so as This vibratory actioncontinues soto cause the vibrator to set up the necessary vibrationresulting from the attraction of the magnet by the armatures. Certain ofthese methods are especially applicable to .code signaling and certainof them appear to be applicable rather to the setting up of anuninterrupted vibration of the vibrator, as will be -more clearlyunderstood from the description hereinafter given.

Thus it will be seen that my invention has right angles to Fig. 3,showing a n1odification. Fig. 5 is a vertical sectional view showinganother modification. Fig. 6 is a section on the line 6-6, Fig. 5. Fig.7 is a sectional view on the line 7 7, Fig. 8, showing still anothermodification. Fig. 8 is a vertical section at right angles to Fig. 7Fig. 9 is a view in section showing the application of my invention to abell-shaped I vibrator. Fig. 10 is a bottom plan view of the apparatusshown in Fig.9, the cap for closing the mouth of the bell being omitted.

Fig. 11 is a sectional detail showing the means of connecting theterminals of the coil with the source of electrical energy. Fig. 12 isanother form of bell'closure to be described below. Fig. 13 is adiagrammatic view of the interrupter showing both the arrangement 'ofthe hand and the continually operated means for breaking the excitingcircuitv Fig. I l-is a sectional elevation of the bow of a submarineboat to I which. my invention, is applied, Fig. 15 being a ,planthereof. Fig. 16. is a horizontal section showing. another applicationof my invention. to a vessel, Fig. 17 being a vertical lsectionon line1717 of Fig. 16. Fig. 18 is a horizontal section showing still anotherapplication of my invention to a vessel, and Fig. 19 .is a vertlcalsection of a pier head housewith my inyention installed therein.

L a For thebest results in submarine signaling it is well known that theoriginator of sound waves must be in contact with a me-' dium of thesame character as that through which the sound waves are to betransmitted. Therefore where a device such as is hereinafter describedis to be used on shipboard it is desirable that the vibrator ordiaphragm shall be immersed in water or equivalent liquid; thus it mayform part'jof one of the walls of the ship below the water line or forma side or part of the side of a water or liquid tank attached to theskin of the ship,

the tank in the latter case being kept full of water; or the vibratormay be wholly surrounded by water. will be hereinafter illustrated. Itwill also be apparent as below more fully described that the vibratorexciter may excite a plurality of vibrators arranged about it to sendout sound waves in different directions or forming the walls of a caseinclosing the exciter, the whole being submerged in a tank or in thewater as at a )ier head.

Referring now to the preferred form of my device as shown in Fig. 1: Thevibrator holder comprises a. casing A of any suitable form adapted to bebolted to the inner wall or skin of the ship or the wall of a tank. Thiscasing is provided with an inwardlyprojecting lip A against the underside of which is bolted the vibrator B by a gasket 7) and bolts 6 Thisgasket answers as a packing. The vibrator is preferably circular inshape, conforming to and closing the end of an opening in the casing A.Such a circular diaphragm held fast at the edges will readily take up agiven rate of vibration and thus originate sound waves of a given pitch.

Upon the casing A is mounted a pair of supports C, each having at itsupper end a bearing of suitable character for the shaft D. Any form ofbearing capable of allowing rapid rotation of the inclosed shaft willanswer this purpose. Upon this shaft is keyed by a key 6 a core E madeof soft iron, upon which is mounted a coilF. Keyed to the core by a key7 are pole pieces G and H, the core being threaded and nuts e and eholding the pole pieces on the core, c1amping them and the coretogether. In Fig. 1 this construction is shown on one side partly insection. The pole piece H and mechanism upon its side of the device isidentical with that which is disclosed by the section. It will be seentherefore that there is here material for an electro-magnet, viz: thecoil F about the core E to which core is attached, the two pole piecesforming the north and south poles of the electro-magnet. The shaft D isconnected to a motor or any source of power whereby it may be rotatedwith great rapidity, These pole pieces are of peculiar construction inthat each pole piece is provided about its edge with a series ofprojections or teeth 9, h between which are a series of recesses 9, H.The vibrator B carries an armature B and when these pole pieces, whichof necessity must i rotate together, .are magnetized, the polnts of onepole piece being opposite those of the other, a series of magneticfields of alternately increasing and decreasing force pass withinattracting range of the armature B, the instant of maximum attractionbeing at the moment when a pair of projections g, h of the pole piecesare nearest the armature,

Such construction after which there is a decrease in magnetic attractionas the projections move away until the next projections in series havecome nearer to the armature than are the receding projections. By thismeans there is a constantly increasing and decreasing attractive forceapplied to the armature which of necessity causes the armature tovibrate and with it the diaphragm, and upon a very rapid rotation of themagnet this vibration of the diaphragm or vibrator becomes sufficient inpoint of speed to give out a musical note. tis evident that thisvibration and hence this musical note will keep up so long as themagnetized pole pieces are caused to rotate. The magnet being preferablyan electro-magnet, however, the vibrations of the vibrator may becontrolled to cause it to give out a sound of greater or less length byinterrupting the electric current by means of which magnetic influenceis excited in the pole pieces.

To connect the coil F with the source of electric energy I perforateeach pole piece as at 9 7L and lead through the perforations, the wallsof which are insulated, the two ends 7, f of the coil F. Each end 7, fis connected to a ring f f mounted upon an insulation f which is carriedby the shaft D, an insulation being provided for each ring. Theinsulation 7 and rings f are attached together and to the shaft D sothat they will rotate with the electro-magnet and yet will be insulatedfrom the shaft. Brushes J J are provided and also wires '1', j whichlead to the dynamo, being attached to the brush holders by the bindingscrews j j The brush holders are attached to the top of the supports Gby means of lugs J J 3 and screws J, the parts being all properlyinsulated as will be understood by those skilled in the art. l Inoperating this mechanlsm power is rapidity according to the diameter thediaphragm and its normal rate of vlbration. YVith the shaft in this formof my invention rotates the core, coil, pole pieces and the rings F, fwith their insulators. The brushes J, J form the electrical connectionbetween the stationary binding screws and the coil. This rotationcausesthe projections on the pole pieces to pass successively the armature Bso that it is influenced by a series of magnetic fields increasing anddecreasing in turn which pass it in regular rotation and cause it toexcite the vibrator to a regular speed of vibration depending of courseupon the i rapidity with which the shaft D is revolvfing. The speed,however, should be in l proper relation to the natural rate of vibrationof the vibrator. The vibration of the vibrator causes sound waves to be0riginatcd which are taken up by the water and applied to the shaft D torotate it with great finally conducted by transmitters or otherreceiving instruments on board other ships 01' at other properlyequipped stations.

In order that ships may communicate one with another or with a lightshipstation or the shore it is necessary that a code be established, andthis apparatus lends itself to thesending of messages, as for example bythe ordinary Morse system, for the reason that the magnetic influencemay be interrupted and the efl'ect-iveness of the magnetic fieldsdiminished materially by interrupting the current which energizes theelectro-magnet. This may be done by means such as are below described. Irealize that there may be residual magnetism in the electro-magnet afterthe current is cut 03;

but in the present instance the magneticattraction in the pole pieces isreduced to such an extent as to nullify its operative power ofattraction for the armature.

Hence by placing an ordinary telegraphic key so as to control thecurrent. in the coil F the action of the vibrator can be reducedperiodically at predetermined intervals to such an extent that it willno longer originate vibrations of sufficient intensity to be perceptiblewith transmitters such as are ordinarily used. Thus it is easy toutilize the Morse code or any other similar code which will enable thesender by a series of long and short efiective vibrations of thevibrator to transmit an intelligible message to any point of receipt, orto use any automatic code such as used on bell buoys.

I ,have shown in Figs. 3 and 4 an apparatus which is in many respectssimllar to that shown in Figs. 1 and 2. It operates in the same generalmanner, but itdiffers from the device of Figs. 1 'and 2 in that the coilF is inclosed in a cylindrical case C suspended by arms C two of whichare carried by supports C, while the third 18 mounted on the arch Cmounted on the supports C. In this case the core olmng the pole piecesrotates with the pole pieces of course but inside of the coil. Inthis,-also, I have shownanother form of armature which is attached tothe diaphragm B. This armature is Y-sha-ped as shown at B the distancebetween the extremities of the armature corresponding to the distancesbe tween two'of the projections; on a pole piece. This can be seen inFig. 3.

In Figs. 5 and 6 the apparatus is reversed, that is to say, the shaft I)carries a series of spokes B- at the end of each of which is an armature13*. Upon the diaphragm or vibrator B is mounted an electro-magnet Fwhich is connected. by wires j, j with i the source of electric current.It will be seen that'in this case the rapid rotation of the armaturesbrings each in turn into and out upon the vibrator vibrations are set upin the vibrator which cause it to move toward and from the axis ofrotation of the wheel of armatures so that in this case the same law ofoperation exists.

In Figs. 7 and 8 still another form of construction is shown, thediaphragm or vibrator B carrying an armature B as shown in Figs. 1 and2. In this case, however, a series of electro-magnets K connectedtogether by wires K is mounted on the periphery of a wheel K carried bythe shaft D, the electro-magnet system being connected as at Fig. 1 withan insulated ring f, f by wires f f brushes J J being used as before tomake contact between the rings dynamo or other source of current. The

precise arrangement of wiring is immaterial, it being merely essentialthat the circuit through the magnets K be completed to the rings f 7'.These last views are merely illustrative and suggestive of the breadthof my invention, the more practical form of which I believe tobe thatshown in Figs. 1 and 2. These views, however, also show a simplifiedform of casing and gasket, the casing being a part of the wall of thewater tank.

' As a means for applying the code signal to a sounder of thischaracter, and by that I mean a means for interrupting a current whichpasses through the coil by which the rotary magnet'is energized, I haveshown diagrammatically in Fig. 13 one form of apparatus useful for thepurpose. In this case'the line 7' runs from one of the tenni nals of thecoil F to the source of electrical energy S. The other terminal of thecoil is connected with the line j which is interrupted by a circuitbreaker and is continued in the line j to the source of electricalenergy S. The circuit breaker shown comprises two terminals 1' 7' whichare connected by the brush contact 7' operated by a relay L. Thiscontact j is connected to an armature Z from which it is insulated andthe armature Z is operated either against gravity or a spring by meansof the relay L. For this purpose the relay magnet L has the insulatedrod L upon which slides a sleeve L connected to and, if desirable,forming a part of the armature Z. A stop Z screwed into the end of therod L limits the movement of the armature. The coil carrying the currentto energize the relay comprises wires P, F one of them Z leading to oneof the wires j of the main circuit and the other leading to the wirethrough an ordinary telegraph key L A shunt j is connected to the wire Zaround the key L and contains acode mechanism I of' well knownconstruction and a switch L to throw the codemechanism into and out ofcircuit so that either automatic code sigcient to operate the circuitbreaker or contact j at the appropriate times and those times will bedetermined either by the operation of the telegraphic key L or by. thecode signal L As shown in this diagrammatic figure the windings of therelay furnish the necessary resistance. When the code signal is to beused the switch L will be closed and the key left open or if the key isto be used to send, for example, telegraphic signals according to theMorse or some other system, the switch L will be opened. By this or somesimilar means the main circuit may be opened and closed at will withoutinjury to the apparatus such as might occur if the current were heavy.

My invention as above described isnseful for submarine boats, and whileit may be introduced into any convenient part of the beat it has seemedto me desirable to introduce it in the superstructure as shown in Figs.14 and 15. In this case the storage battery by means of which the motoris operated is shown at M the wires, m, m leading from it directly tothe motor M by which power is applied to the shaft D carry ing themagnet of which the pole pieces G and H are shown, B, B, being thevibrators. Inthis case it will be noted that there are four vibratorslocated at ninety degrees on the four sides of the pole pieces G, H,form ing a watertight case, all of which will be operated simultaneouslywhen the coil is energized and the pole pieces become magnetizedthereby; and it is necessary for efficiency that the projections g, h onthe pole pieces shall be a multiple of four in number in order that theymay work in harmony on the diaphragms. In fact, this should always be sowhen more than. one diaphragm is used, 1 I have not shown the details ofconstruct-ion nor the location of the circuit breaker in the coilcircuit .as the apparatus is preferably like that shown in Fig. 13 andmay be'in any convenient part of the boat. In this case the diaphragmsbecome the walls of the watertight chamber, the space about the chamberfilling with water when the submarine boat is submerged, so that thevibrations of the'diaphragms B are delivered directly into the liquidsurroundin the diaphragms from j which they are d sseminated in alldirections.

In Figs. 16 and 17 I have shown other forms of utilizing this invention.As will be seen from Fig. 17, the sounder in this case is located in thefore peak, and from Fig. 16 it will be seen that vibrations aredelivered into two tubes both together forming a water tank, these tubesbeing lettered, P, P Both of these tubes may be open like tube P or bothmay be closed as at- P at the outer end. If both are closed means shouldbe provided for keeping them full of water or other liquid so that thevibrations will be received in the liquid as before. In this case butone diaphragm B is used. In Fig. 18 there is a similar arrangement 'inwhich, however, the tubes P, P lead to opposite sides of the bow of theship, the apparatus having two diaphragms in this case, whereas in theformer case only one diaphragm was necessary. In this latter case thereis shown at Q the diagrammatic representation of an ordinary gate valveadapted to close the tube P to the passage of water so that shouldrepairs be necessary to the apparatus the gate valve can be closed andthe diaphragm forming the end of that tube can be repaired as occasionmay require without opening a hole in the side of the ship. Such a valveQ, should be used in any arrangement in which the outer end of the tubeis open; as in Fig. 16 where the tube P is open. Valves of thisconstruction are well known and henceneed not be described.

In Fig. 9 I have shown the application of my invent-ion to a bell-shapedvibrator. In this case the" vibrator is lettered B and is of bell-likecharacter and constructed preferably bf bell metal. As shown it carriesfour armatures B equidistant from each other and each secured into theinner surface of the bow.

The electro-magnet comprises two pole pieces G H each similar to polepieces G, H above described and having similar teeth and-recesses, thoseon the pole piece H being shown at h and h in Fig. 10. The. pole iecesGr and H are connected by the core The pole piece G however is smallerin diameter than the pole piece H so that the electro-magnet conformssomewhat to the interior shape of the bell.

,The electro-magnet is carried by the h ollow shaft D to which it isattached between nuts d, d which clam its elements together, means ofany sultable character heing'provided so that the electro-magnet andshaft will rotate together.

F is the coil of the electro-magnet, the terminals f f of which pass upthrough the hollow shaft D to rings f f mounted near the upper end ofthe shaft D but insulated therefrom as before, brushes J, J 1 beingprovided of the same character as those shown in Fig. 1 connected bywires 9', y' to of the electro-magnet rapid vibration of the sound bowof the bell,

the source of electrical energy to lead the current to the coil F.

The shaft D passes up through bearings D in the upper part of the belland into a box D in which is a motor comprising -a casing M supported onthe floor of said box and carrying suitable fields m, the armature mbeing located onthe shaft D This motor may be of any suitableconstruction and current may be supplied to it in' any suitable way, forexample, t rough a cable m Its details will be understood by all skilledin the art, and henceare not described.

Upon the shaft is also located a governor M to regulate the speed ofrotation of the shaft. The rings 1, f above referred to are fordonvenience located at the upper end of the shaft. A collar m held tothe shaft by a set screw and resting on the bottom of the box D holdsthe shaft D and the parts connected to it in proper relation to theircooperating parts. The operation of this form of my invention is simple.'The motor contained in the casing M being supplied with current causesthe rotation of the shaft D and as the current is su plied to the coil FGE, H it causes the in the manner above described. .The bottom of thebell is closed by a rubber or metal cap (1 which may be flat as shown inFig. 9 or corrugated as shown at d in Fig. 12, to prevent the inflow ofthe water in which the apparatus is suspended.

This apparatus is also valuable for signaling from pier heads forsteamships or ferry boats. In this case the apparatus is constructedvery much as in Fig. 14, the'rotary magnet, etc. beingarranged. in aclosed watertight box having diaphragms B onfour sides, the connectionsresembling those v in Fig. 9. The shaft D as shown in Fig. 19 isvertical and hollow carrying within it the two wires P, f leading to thecore andbeing connected at their outer ends to theicol with the sourceof electrical energy through 1 lector rings i 1, upon which the brushesJ, J bear. These brushes, are connected a code signal mechanismrepresented diagrammatically at R operated by a motor I do not intend tolimit it toany one embodiment. On the contrary it is capable of manyconstructions and many applicat ons.

In its'simplest form it comprises an elec- The catedabove that it mayform one wall of the 7 5 tank. Thus in the form of vibrator shown inFigs. 1 and 2 the casing A may be bolted to the side of the ship, theinclosure so formed being the tank which may be filled with water orother liquidin which the sound waves begin their passage to the Wateroutside the ship and to. the receiving station wherever it may be. .Soin Figs. 3 to 8,-

though the casing is of different form and may be the wall of a tank ora part of the side of the ship itself, the diaphragm be comes a portionof the liquid-retaining mechanism or of the side of the ship and itsvibrations are directly communicated to the liquid. In all cases Wherethe sound-producing diaphragm is in contact with a body of water held ina tank or similar means, the sound-producing device is-f0r allpracticahpurposes immersed or locatedin the second body of liquid; and hence Iregard my invention as bein within the scope of the invention set fortin the patent to Millet and Mundy, No. 773,580, dated November 1, 1904,on which my invention is an improvement which I believe will befound ofgreat advantage in actual practice.

The vibrator also lends itself to-the con.- struction of a casing thesides of which each contain a vibrator and which may be madewatertightto inclose the rotary "magnet or other mechanism for exciting vibrationsin 4 the vibrator, such a construction being shown in Figs. 14, 15 and17, or to such a modification of this construction as is shown in Fig.18. It is also evident that instead of a special vibrator thevibration-producing mechanism may set up vibrations in a prop erly baredportion of the skin of a shipi What I claim as my invention is 1. Asounder comprlsing, in combination,

' a vibrator-and means for vibrating the same,

said vibrating means comprising a single electro-magnet and an armaturecooperating simultaneously with both poles of said magnet, one of saidparts being carried by said vibrator, means for supplying adirectconstant current to said electro-magnet during the operation of saidsounder, and means independent of the sound producing vibrations of saidvibrator for repeatedly varying the relative position of said armatureandthe'magnetic field of said magnet.

23A sounder comprising, in combination,

a vibrator and means for vibrating the same, said vibrating meansComprising a single electro-magnet and an armature cooperatingsimultaneously with both of thepoles of said magnet, one of said partsbeing carried by said vibrator, means for moving the other of said partswith respect to said first-named part,- and means for supplying a directconstant current to said electro-magnet during the operation of saidsounder.

' 3. A sounder comprising, in combination, a vibrator capable ofmagnetic attraction, a single elect-ro-magnet both poles of which arearranged to attract said vibrator simultaneously, means for supplying adirect constant current to said electro-magnet during the operation ofsaid sounder, and means independent of the strength and continuity ofsaid current for repeatedly varying the relative position of saidvibrator and the magnetic field of said magnet.

4. A sounder comprising, in combination, a vibrator capable of magneticattraction, a single electro-magnet both poles of which are arranged toattract said vibrator simultaneously, means for moving saidelectromagnet with respect to said vibrator to varyv its attractiveforce therefor, and means for supplying a direct constant currentto saidelectro-magnet during the operation of said sounder.

5. A sounder comprising a vibrator and means-for vibrating the same,said vibrating meansco-mprising an electro-magnet'and an armature, oneof said parts being carried by said vibrator, means for supplying adirect constant current to said eleotro magnet during the operation ofsaid sounder, and means independent of the strength and continuity ofsaid current for repeatedly varying the relative position of saidarmature and the magnetic field of said magnet, in combination withmeans to interrupt said current and thereby to interrupt the operationof said sounder.

6. A sounder comprising a vibrator and means for vibrating the same,said vibrating means compfisingan electro-magnet and an armature, one ofsaid parts being carried by said vibrator, means for moving the other ofsaid parts with respect to said first-named part, and means forsupplying a direct constant current to said electro-magnet during theoperation of said sounder, in combination with means to interrupt saidcurrent and thereby to interrupt the operation of said sounder.

7. A sounder comprising a vibrator capable of magnetic attraction, anelectromagnet arranged to attract said vibrator, means for supplying adirect constant current to said electro-magnet during the oper' ation ofsaid sounder, and means independent of the strength and continuity ofsaid current for repeatedly varying the relative position of saidvibrator and the magnetic field of said magnet, in combination withmeans to interrupt said current and thereby to interrupt the operationof said sounder.

8. A sounder comprising a vibrator capable of magnetic attraction, anelectromagnet arranged to attract said vibrator, means for moving saidelectro-magnet with respect to said vibrator to vary its attractiveforce therefor, and means for supplying a direct constant current tosaid electromagnet during the operation of said sounder, in combinationwith means to interruptsaid current and thereby to interrupt theoperation of said sounder.

9. A sounder comprising a vibrator capable of magnetic attraction, anelectromagnet having a core provided with a series of projections, saidelectro-magnet being rotatable on an axis coincident with the'axis ofsaid core to bring said projections successively adjacent said vibrator,and means for supplying a direct constant current to said electro-magnetduring thepperation of said sounder.

10. A sounder comprising a vibrator capable of magnetic attraction. anelectromagnethaving a core provided with a series of oppositely arrangedprojections at each pole, said electro-magnet being rotatable on an axiscoincident with the axis of said core to bring said projectionssuccessively adjacent said vibrator, and means for supplying a directconstant current to said electromagnet during the operation of saidsounder.

11. As a means of vibrating a vibrator of the kind described, anelectro-magnet comprising a'core carrying at each end a disk, thesurfaces of said disks being opposed to each other, each disk having aseries of projections from its edge, the projections on each disk beingopposite the projections on the opposing disk, said core carrying acoil, and means for electrically exciting said coil and means forrotating said disks.

12. As a means of vibrating a vibrato of the kind described, anelectro-magnet comprising a core carrying at each end a concave disk,the concave surfaces of said disks being opposed to each other, eachdisk having a series of projections from its edge, the projections oneach disk being opposite the projections on the opposing disk, said corecarrying a coil, and means for electrically exciting said coil and meansfor rotating said disks.

13. As a means for vibrating a vibrator of the kind described, anelectro-magnet comprising a core carrying at each end a disk, each diskhaving a series of projections from its edge, the projections on eachdisk being opposite the projections on the opposing disk, said corecarrying a coil, means for electrically exciting said coil to prising ashaft, a core, two disks located on said shaft one at each side of saidcore, each dISK having a series of projections from its edge, theprojections on each disk being opposite the projections on the'opposingdisk, said core carrying a coil, means for exciting said coil and meansfor periodically interrupting said coil -exciting means as set forth.

'15. A sounder comprising a controllable vibrator'and a rotaryelectro-magnet, said magnet having two poles in parallel planes eachpole having a plurality of projections in opposed relation to eachother, said vibrator being located adjacent to the path of the magneticfields of said projections.

16. A sounder comprising a controllable vibrator and a rotaryelectro-magnet, said magnet having two poles in parallel planes atsubstantially right angles to the plane of said vibrator, each polehaving a plurality of projections in opposed relation to each other,said vibrator being located adj acent to the path of the magnetic fieldsof said projections.

17. In a submarine signaling device, a plurality of vibrators capable ofmagnetic attraction and one surface'of each of which is in contact Witha liquid through which rality of attractablev vibrators one surface ofeach of which is'in contact with a liquid through which sound Waves areto be sent,

and means for causing vibrations of said.

vibrators to.originate sound waves comprising a single rotaryelectro-magnet having two poles in parallel planes, each pole having aplurality of projections in opposed relation to each other, saidvibrators being located about said rotary magnet and ad-' r jacent tothe path of the magnetic fields of said projections. 1

EDWARD o. WOOD. I

Witnesses H. J. W. FAY, H. H. STEWART.

